Podcasting Scene Setup

[titan]

So... I'm very new to GIMP and anything creative.  I'm trying to setup a template for my wife.  She wants to podcast with a custom background, once or twice a week.  After all the tutorial videos and messing around with the app for a few days, I've decided to do this with the setup in the picture. layers: title, subtitle, footer, overlay, image of whatever for the wallpaper... Then, I created a channel for her host/co-host selection areas.  That way, I can just create a new layer from visible based off all her data that changes every few days, and apply a layer mask from the channel I created. 

My issue is.. I've found myself wanting to adjust the selected area in a channel that has multiple selections in it.  When I go into my channel and hit replace selection with this channel, and have multiple selections on the screen, I cannot edit just one of the selections.  Is there a way to do that? or am I stuck recreating the final channel from scratch?  I intend on making overlay channels for 2-5 people with and without sharing a desktop for OBS scenes (8 channels).

It's not horribly complicated to remake selection channels, but it takes a good bit of work to get them lined up properly (making sure the scale on each selection is right and the spacing from the edges all line up).... and it would be nice to move individual parts of the selections like I can when I'm creating them.  That way I can just click select save to channel again after I make some small tweaks.

[Ofnuts]

You can do several partial selections, save them to channels, and then create the final selection by combining (some of) them. See here.

You can move several channel together. Jut chain-link them, make them visible and select one of them, then in the Move tool use "Move active layer" (which in this case won't be a layer). The only catch is that channels are clipped to the canvas and during the move the preview only shows the one you are dragging (the others are moved only at the end).

[rich2005]

Hmm..I might have the concept wrong Since the channels end up as masks I might dispense with them and go straight for groups and layer masks. The only 'tweak' in this the main image group is in screen mode.

   

Keeping everything in groups, the individual masked areas can be toggled on / off  and if required the mask edited as required. 30 second animation of that https://i.imgur.com/9gmzaxy.mp4

Edit: Missed out the tweaking location Move tool with move the active layer toggle on...and a bit of repair with the paint tool. https://i.imgur.com/iZhSLaG.mp4

...and for reference that image https://u.pcloud.link/publink/show?code=...Sib0kg5sIy  6 Mb Gimp .xcf.gz file.